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1.
以淀粉为主链、甲基丙烯酰氧乙基三甲基氯化铵(DMC)为功能单体、苯乙烯(St)和丙烯酸丁酯(BA)为改性单体,采用种子乳液共聚法制备了无皂淀粉基阳离子苯丙乳液。讨论了反应条件对该乳液稳定性及乳胶膜性能等影响,并采用红外光谱(FT-IR)法对乳液聚合物结构进行了表征。结果表明:当m(DMC)∶m(淀粉+St+BA)=0.8∶1、m(淀粉)∶m(St+BA)=1.00∶3、m(St)∶m(BA)=1.50∶1、反应温度为80℃、w(引发剂)=2%且m(过硫酸钾KPS)∶m(NaHSO3)=2∶1时,改性乳液的综合性能最佳。  相似文献   

2.
A batch emulsion copolymerization for the preparation of styrene-n-butylacrylate (St/BA) copolymer latexes is investigated. A series of n-butylacrylate-styrene copolymer latexes were obtained by emulsion copolymerization in the presence of K2S2O8 (KPS) as initiator and with/without emulsifier (sodium lauryl sulfate). The effect of such preparation conditions as initiator concentration, the St/BA ratio, reaction temperature, agitation rate, and emulsifier concentration on the polymerization rate, particle size of copolymer latex, and molecular weight distribution of the resulting copolymer (∼ 80% conversion), respectively, is systematically studied using fractional factorial design methodology. Fractional factorial analysis indicates that the effects of the St/BA ratio, reaction temperature, emulsifier concentration, as well as the two-factor interaction of temperature and emulsifier concentration, are the key variables influencing the polymerization rate. At ∼ 80% monomer conversion, statistical analysis clearly isolates emulsifier concentration as the dominant factor affecting average particle size of copolymer latex; results also indicate that the effects of the St/BA ratio, reaction temperature, and emulsifier concentration are major effects influencing the polydispersity of polymer molecular-weight distribution. For 7.30 g KPS/100 g monomer and 500 rpm agitation rate, the conditions for minimizing molecular-weight distribution (∼ 80% conversion) occur for a reaction temperature, St/BA ratio, and surfactant concentration of 70°C, ∼ 3.59/1, and ∼ 2.08 g/100 g monomer, respectively, generating a minimum molecular-weight polydispersity of ∼ 3.0. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 551–563, 1998  相似文献   

3.
丙烯酸酯乳液胶粘剂的合成及其性能研究   总被引:3,自引:2,他引:1  
以丙烯酸丁酯(BA)、甲基丙烯酸甲酯(MMA)、苯乙烯(St)、丙烯腈(AN)和丙烯酸(AA)为单体,十二烷基硫酸钠(SDS)为乳化剂,过硫酸钾(KPS)为引发剂,通过半连续乳液聚合方法合成了丙烯酸酯乳液胶粘剂。研究了软硬单体配比、不同硬单体以及功能单体AA对胶粘剂性能的影响。研究结果表明,当m(BA)∶m(MMA)∶m(AN+St)=75∶15∶10[其中m(AN)∶m(St)=1∶3]、w(AA)=2份时,制备的乳液胶粘剂具有较好的剪切强度、拉伸强度和耐水性。  相似文献   

4.
Styrene (St)/butyl acrylate (BA) copolymers were prepared by adding triethoxyvinylsilane (TEVS), trimethoxyvinylsilane (TMVS), and triphenylvinylsilane (TPVS), each one through emulsion copolymerization. The polymerization was performed with methacrylic acid and auxiliary agents at 80°C in the presence of potassium peroxodisulfate as the initiator. Nonylphenol ethylene oxide‐40 units (NP‐40) and sodium lauryl sulfoacetate were used as nonionic and anionic emulsifiers, respectively. The resulting copolymers were characterized by using Fourier transform infrared spectroscopy. Thermal properties of the copolymers were studied by using thermogravimetric analysis and differential scanning calorimetry. The morphology of copolymers was also investigated by optical microscopy, and then the effects of silicone kinds and concentrations on the properties of the St/BA emulsion copolymers were discussed. The obtained copolymers have high solid content (50 %) and can be used in emulsion paints as a binder. The comparison of three different vinyl silanes indicates that the TEVS influences on the copolymer properties more than the others. The calculations of monomer conversion and monomer conversion versus time histories indicate that by increasing the silicone concentration, the polymerization rate decreases. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

5.
水性上光油用苯丙共聚乳液的合成及性能表征   总被引:2,自引:0,他引:2  
以苯乙烯(St)、丙烯酸丁酯(BA)和马来酸酐(MAH)为共聚单体,过硫酸钾(KPS)为引发剂,十二烷基硫酸钠(SDS)/壬基酚聚氧乙烯醚(OP-10)为复合乳化剂,采用半连续加料的乳液聚合法合成出一种水性上光油用苯丙共聚乳液。考察了玻璃化转变温度(Tg)、引发剂和乳化剂含量等对该乳液单体转化率、平均粒径、黏度和表干时间等影响,并对该乳液的热稳定性能进行了研究。结果表明:当w(引发剂)=0.6%、w(复合乳化剂)=1.2%和m(MAH)∶m(BA)∶m(St)=4.6∶36.3∶50.5时,该乳液具有良好的综合性能,完全满足水性上光油的使用要求,并且可在高温环境中使用。  相似文献   

6.
The concentrated emulsion copolymerization of butyl acrylate and vinyl acetate with an ammonium persulfate/sodium hydrogen sulfate mixture as a redox initiator, with a sodium dodecyl sulfate/cetyl alcohol mixture as a compound surfactant, and with poly(vinyl alcohol) as a liquid film reinforcer was carried out at lower temperature. In less than 3 h, the polymerization conversion was greater than 95%. The effects of the surfactant, the initiator, the volume fraction of the monomer, and the temperature on the stability of the concentrated emulsion, the kinetic process, and the average size of the latices were examined. The morphology of the polymer particles was observed by transmission electron microscopy, and the average size and distribution of the particle diameter were measured by photon correlation spectroscopy. The kinetic equation was Rp = k[M]0.38[I]0.89[E]?0.80 at 30°C (where Rp is the polymerization rate, [I] is the initiator concentration, [M] is the monomer concentration, and [E] is the concentration of the compound surfactant), and the apparent activation energy was 22.69 kJ/mol. The thin‐layer polymerization of the concentrated emulsions, which enabled the removal of the heat of polymerization, was performed first. In comparison with test‐tube polymerization, thin‐layer polymerization provided a more regular morphology of the polymer particles. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 570–576, 2004  相似文献   

7.
用甲苯二异氰酸酯(TDI)、聚丙二醇(N_(210))、丙烯酸-β-羟乙酯(β-HEA)、聚乙二醇-600(PEG-600)分三步制得含双键的非离子型聚氨酯PUAG,然后与苯乙烯单体,在MS-1、十六醇(CA)、聚乙烯醇(PVA- 1788)作乳化体系,以偶氮二异丁腈(AIBN)为引发剂,在55℃下引发聚合。研究了NCO/OH摩尔比、复合乳化剂质量浓度、引发剂质量浓度、内相比、聚合温度、PUAG的量等因素对聚合稳定性影响。用透射电子显微镜(TEM)观察聚合物乳胶粒子的形态,用红外光谱证明了PUAG的共聚物的生成。  相似文献   

8.
以苯乙烯(St)和丙烯酸丁酯(BA)为主单体,以丙烯酸和丙烯酸-2-羟基丙酯为功能单体制备了St-BA共聚乳液,研究了可聚合乳化剂烯丙氧基壬基酚聚氧乙烯(10)醚单磷酸(ANPEO10-P1)对共聚乳液的聚合稳定性、化学稳定性、羧基分布及乳胶膜耐水性、剥离强度等性能的影响。结果表明:与常规乳化剂十二烷基硫酸钠(SDS)相比,使用可聚合乳化剂ANPEO10-P1能有效地改善乳液的性能。通过电导滴定发现,乳化剂对乳液不同区域的羧基分布有较大的影响,因而影响乳胶膜的耐水性和剥离强度。  相似文献   

9.
Stable concentrated emulsions of polymerizable polysiloxane‐containing polyurethane (PUASi)/Styrene (St)/Methyl methacrylate (MMA) were prepared using sodium dodecyl sulphate (SDS)/nonyl polyoxyethylene ether (OS15)/polyvinyl alcohol (PVA) as composite surfactant and azobisisobutyronitrile (AIBN) as initiator. A novel polymerization method, thin layer polymerization was used to carry out the concentrated emulsion copolymerization at 55°C. The effects of TDI/PPG molar ratio, surfactant concentration, different kinds of surfactants, and temperature on polymerization stability were studied. The effects of the thickness of the thin layer, the outside temperature of the reactor, as well as polymerization environment on the volatilization rate of water, and monomer in the system were investigated. The conversion‐time relationships of the thin layer polymerization and the tube polymerization, as well as the effect of polymerization environment on the polymerization rate were also investigated. The morphology of latex particles was determined with transmission electron microscope (TEM). © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

10.
A graft copolymer was synthesized by graft copolymerization of starch with styrene (St) and butyl acrylate (BA), using ferrous sulfate‐hydrogen peroxide redox initiation system. The starch was pregelled in the presence of acrylonitrile (AN) in aqueous alkali at high temperature before graft polymerization. Major factors affecting the polymerization reaction were investigated. It was found that a graft copolymer with higher percentage conversion (PC), graft efficiency (GE) and graft percentage (GP) was obtained by controlling the initiator concentration, concentration, and ratio of monomers and polymerization temperature. The optimum conditions were as follows: H2O2 concentration, 12%; monomer concentration, 120%; St/BA ratio, 1 : 1; polymerization temperature, 65°C. Fourier transform infrared spectroscopy and NMR analyses were used to gain information on the structure of the products. It was demonstrated that St, BA, and AN had been successfully grafted onto starch and ? CN had been saponified into ? CONH2 and ? COO? to a certain degree when pregelling. Scanning electron microscope micrographs showed the coarse structure and broad network. The graft polymerization took place on the surface of starch granule and led to amorphization of the starch structure. Graft polymer had better thermal stability and was endowed with pseudo‐plasticity. It was observed that the starch graft copolymer offers good properties such as water resistance as surface‐sizing agent. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

11.
以甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)、丙烯酸(AA)及丙烯酸羟乙酯(HEA)为单体,以十二烷基硫酸钠(SLS)、OP-10和正辛醇的复合物为乳化剂,当m(BA)∶m(MMA)∶m(AA)∶m(HEA)=50∶50∶3∶10、w(乳化剂)=13%、反应温度为80℃及反应时间为3h时,合成了可用于超高相对分子质量聚乙烯纤维粘合涂层的水乳型聚丙烯酸酯微乳液,单体转化率为99 8%,乳胶粒径为30nm,乳液膜的玻璃化温度为-28℃,应用工艺简单,涂层粘附性好、柔软、耐磨。  相似文献   

12.
Multistage emulsion polymerization was used to prepare ultra‐high molecular weight foam regulator of low cost, with methyl methacrylate (MMA), butyl acrylate (BA), styrene (St) as main raw materials. Ubbelohde viscometer, dynamic light scattering, infrared and raman spectra, TEM, DSC, TGA, and GPC were all used to characterize constituent and structure, morphology, and molecular weight. As a result, when the ratio of soft monomer (BA) and hard monomer (St + MMA) is 1:3, MMA:St = 4:1, potassium persulfate (KPS): 0.15%, sodium hydrogen sulfite (SHS): 0.05%, azodiisobutyronitrile (AIBN): 0.15%, divinyl benzene (DVB): 0.3%, the final product terpolymer has obvious core‐shell structure and ultra‐high molecular weight (Mw = 1,400,000). This kind of foam regulator showed improvements in the melt strength, prevention of bubble coalescence and reduction on cost when compared with the traditional. Finally, the coefficients of poly (methyl methacrylate‐butyl acrylate‐styrene) terpolymer's Mark‐Houwink equation were calculated with tetrahydrofuran (THF) solvent at 25 °C. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44479.  相似文献   

13.
在少量甲基丙烯酸钠盐的存在下,成功合成了具有高稳定性、高透明性的聚(苯乙烯/丙烯酸丁酯)P(St/BA)无皂共聚乳液。同时,还对不同配方的乳液及其涂膜的综合性能进行了研究,总结了组成与性能之间的对应关系,并着重讨论了单体组成与乳液表面能、乳胶粒尺寸之间的关系。结果表明:随单体配比中St含量的增加,乳液接触角和乳胶粒粒径减小;乳胶粒具有均一的尺寸,并显示出明显的核壳结构。通过对苯丙无皂乳液组成与性能关系的研究,积累了一定量的理论数据,为无皂乳液产品的进一步研究开发提供了条件。  相似文献   

14.
以丙烯酸丁酯(BA)为软单体、丙烯酸甲酯(MA)为硬单体、2-乙基己烷丙烯酸酯(2-EHA)为特软单体、丙烯酸(AA)为亲水单体、二甲基丙烯酸乙二醇酯(EGDM)为交联剂、平平加(O-25)和十二烷基硫酸钠(SDS)为复合乳化剂、过硫酸钾(KPS)和偏重亚硫酸钠(SM)为氧化还原型引发剂,采用乳液共聚法合成环保型静电植绒胶。结果表明:当m(BA)∶m(MA)∶m(2-EHA)∶m(AA)∶m(EGDM)∶m(0-25/SDS)∶m(KPS/SM)=100∶40∶4∶8∶3∶(26/7)∶(1/1.0)时,胶粘剂稳定性较好;此时静电植绒织物中无游离甲醛含量和APEO含量,其摩擦牢度2 500次且柔软度为4~5级,符合生态服装面料的使用要求。  相似文献   

15.
A new silicone containing macromonomer, 4‐(methacrylamido) phenoxy polymethylhydrosiloxane (4‐MPMHS) with a vinyl group, was successfully synthesized. Then poly (silicone‐co‐styrene‐co‐butylacrylate) with montmorillonite, P (Si‐co‐St‐co‐BA) with MMT nanocomposite emulsion was prepared by in situ intercalative emulsion polymerization of styrene (St), butyl acrylate (BA), and 4‐MPMHS, in the presence of organic modified montmorillonite (OMMT) with different OMMT contents (0, 0.5, 1.0, 1.5, and 2 wt %). Potassium persulphate (KPS) was used as an initiator and sodium lauryl sulfoacetate (SLSA) and nonyl phenol ethylene oxide—40 U (NP‐40) were used as anionic and nonionic emulsifiers, respectively. The resulting macromonomer was characterized by elemental analysis, Fourier transformer infrared (FT‐IR), proton (1H NMR), and carbon (13C NMR) nuclear magnetic resonance spectroscopes. The OMMT was characterized by FT‐IR and X‐ray diffraction (XRD). The nanocomposite emulsions were characterized by using Fourier Transform infrared spectroscopy (FT‐IR), laser light scattering, and surface tension method. Thermal properties of the copolymers were studied using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) and then the effects of OMMT percent on the water absorption ratio and drying speed were examined. Results showed that OMMT could improve the properties of emulsion. In other words, the properties of nanocomposite emulsions were better when compared with those of the silicone‐acrylate emulsion. The property of nanocomposite emulsion containing 1 wt % OMMT was the best one, and the following advantages were obtained: smaller particle size, faster drying speed, smaller surface tension, and improved water resistance by the incorporation of OMMT. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

16.
Cationic copolymer emulsions of St, BA, AA, and GMA were successfully synthesized via semi‐continuous emulsion polymerization. The properties of synthesized cationic emulsions were characterized by monomer conversion and solid content, differential scanning calorimeter, particle size and distribution, zeta potential, and centrifugal stability. The film performance of the cationic emulsions formed on cotton fiber surface was observed by scanning electricity microscopy. The influence of cationic emulsions on the color data, K/S values and rubbing fastness of dyed cotton fabrics was also investigated. The results show that P (St‐BA‐AA‐GMA) emulsion had larger particle size and higher zeta potential than P (St‐BA‐AA) emulsion. When the films were formed at room temperature, P (St‐BA‐AA‐GMA) emulsion film had better performance than P (St‐BA‐AA) emulsion film. The addition of GMA monomers improved the film performance. P (St‐BA‐AA‐GMA) emulsion films formed at 120 °C after acetic acid solution treatment had the best water resistance. Dyed cotton fabrics pretreated with P (St‐BA‐AA‐GMA) emulsion had better pigment dyeing performance than those pretreated with P (St‐BA‐AA) emulsion. It demonstrates that the addition of GMA monomers further improved the effect of pigment dyeing for cotton fabrics with cationic emulsions as binders. With the increase of P (St‐BA‐AA‐GMA) concentration, the color performance of dye fabrics improved while the rubbing fastness decreased a little. But, the handle and fastness still meets the use standards for consumers. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44987.  相似文献   

17.
以过硫酸钾(KPS)和亚硫酸氢钠(NaHSO3)为自由基聚合体系的氧化-还原型引发剂,以十二烷基硫酸钠(SDS)和脂肪醇聚氧乙烯醚硫酸钠(AES)为阴/非离子型复合乳化剂,制备甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)和甲基丙烯酸(MAA)共聚物乳液。研究了引发剂种类及用量对该乳液性能及聚合过程等影响,探讨并提出了酸性条件下丙烯酸酯乳液体系的新型引发机制。结果表明:在其他条件保持不变的前提下,当m(KPS):m(NaHSO3)=1.00:0.45、w(KPS+NaHSO3)=0.6%时,乳液的单体转化率(98%)和黏度(5.900 Pa.s)相对最高,反应时间(2.0 h)相对较短且初始聚合温度(60℃)相对最低,此时乳液质量最稳定。  相似文献   

18.
Summary In this study, stable concentrated emulsions of methyl methacrylate and butyl acrylate (MMA-BA) were first prepared using sodium dodecyl sulfate/cetyl alcohol (SDS/CA) as composite surfactants and polyvinyl alcohol (PVA) as liquid film reinforcer. A novel polymerization method, thin layer copolymerization of the concentrated emulsion was subsequently carried out with benzoyl peroxide/N, N’-dimethyl phenylamine (BPO/DMA) as redox initiators at low temperature. The effects of the thickness and area of the thin layer, the outside temperature, as well as environment of the polymerization on the amount of volatilization of water and monomer in the system were investigated. It has been found that the liquid film reinforcers and the polymerization environment were responsible for the polymerization stability. In addition, the conversion-time relationships of the thin layer polymerization and the tube polymerization, as well as the effect of polymerization environment on the polymerization rate were also investigated. The size and distribution of particle diameter and morphology of latex particles were determined with transmission electron microscope (TEM).  相似文献   

19.
核壳型苯丙乳液的制备   总被引:2,自引:0,他引:2  
用种子乳液和预乳化工艺,以苯乙烯(St)、丙烯酸丁酯(BA)、甲基丙烯酸甲酯(MMA)、丙烯酸(AA)为单体,十二烷基硫酸钠(SDS)、烷基酚聚氧乙烯醚(OP-10)为混合乳化剂,过硫酸铵为引发剂,制备了具有核壳结构的苯丙乳液。探讨了乳化剂、引发剂、丙烯酸对乳液性能的影响。合适的反应条件为:MMA∶BA∶St∶AA=14∶25∶16∶2,乳化剂用量为3.2%,引发剂用量0.35%~0.42%,温度80℃。  相似文献   

20.
Yingwu Luo  Huajun Xu  Bin Zhu 《Polymer》2006,47(14):4959-4966
Unlike conventional emulsion polymerization, monomer droplet nucleation becomes dominant in miniemulsion polymerization, offering the miniemulsion polymerization a great advantage over conventional emulsion polymerization when incorporating alkoxysilane monomer, which can easily undergo premature hydrolysis and condensation reactions, into polymer latex. The extensive premature hydrolysis and condensation can lead to the issue of the colloidal instability. In this article, the influence of monomer types on the colloidal stability in the miniemulsion co-(or ter-)polymerization was investigated when incorporating alkoxysilane monomer into styrene or acrylate latex. In the cases of butyl acrylate (BA)/γ-methacryoxypropytrimethoxysilane (MPMS), BA/methyl methyacrlate (MMA)/MPMS, and BA/styrene (St)/MPMS miniemulsion polymerization, nearly no coagulum was observed. The obtained latex had a long shelf life. However, the coagulum was formed in the late stage of MMA/MPMS and St/MPMS miniemulsion copolymerization. The shelf life of the corresponding latex was short. The selection of the main monomer, which can fast consume alkoxysilane comonomer, was critical to obtain the stable latex. In this way, the alkoxysilane groups were completely buried in particles thus the coagulation caused by condensation reactions derived from the alkoxysilane hydrolysis among particles was suppressed.  相似文献   

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